code: def forward(self, x):
      x = self.conv(x)
      x = self.bn(x)
      return x
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import math
  import paddle
  from paddle import nn, ParamAttr
  from paddle.nn import functional
  import numpy
label_desc: Use image node_id 2 for calling the ConvBNLayer obj's underlying member method code with example usage: obj.forward(x) and returns: x